8921557 has 4 divisors (see below), whose sum is σ = 8952300. Its totient is φ = 8890816.

The previous prime is 8921467. The next prime is 8921569. The reversal of 8921557 is 7551298.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4977361 + 3944196 = 2231^2 + 1986^2 .

It is a cyclic number.

It is not a de Polignac number, because 8921557 - 2²³ = 532949 is a prime.

It is a super-3 number, since 3×8921557³ (a number of 22 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8925557) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14932 + ... + 15517.

It is an arithmetic number, because the mean of its divisors is an integer number (2238075).

Almost surely, 2^8921557 is an apocalyptic number.

It is an amenable number.

8921557 is a deficient number, since it is larger than the sum of its proper divisors (30743).

8921557 is a wasteful number, since it uses less digits than its factorization.

8921557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30742.

The product of its digits is 25200, while the sum is 37.

The square root of 8921557 is about 2986.8975543195. The cubic root of 8921557 is about 207.4022920251.

The spelling of 8921557 in words is "eight million, nine hundred twenty-one thousand, five hundred fifty-seven".